The present invention relates to a heat exchanger within a suction accumulator particularly adapted for use in a refrigeration system.
Most compressors used in refrigeration systems are designed for the compression of gaseous refrigerant. Under some circumstances, however, a certain amount of liquid may flow from the evaporator into the inlet of the compressor so as to cause a condition known as slugging. If this occurs after the system is shut down, large quantities of condensed refrigerant return through the suction line to the crankcase of the compressor, and when the compressor is restarted, the large quantity of liquid refrigerant present therein results in abnormally high pressures which frequently causes blown gaskets, broken valves, and the like.
Suction accumulators prevent this from occurring by providing a reservoir for the liquid refrigerant at the inlet to the compressor, and serve to separate the gaseous and liquid components of the refrigerant so that only the gaseous component and a controlled amount of liquid is admitted to the inlet of the compressor. One type of accumulator comprises a vessel having a generally U-shaped tube mounted therein, wherein one end of the tube is connected to an outlet tube leading from the vessel, and the other end of which is open to the interior of the vessel. As the incoming liquid refrigerant flows into the vessel, it collects in the bottom thereof whereas the gaseous component is carried off through the tube to the outlet. This type of suction accumulator is disclosed in U.S. Pat. No. 3,420,071, for example.
Another type of suction accumulator comprises a storage vessel having a generally vertical weir member located between the vessel inlet and outlet and which forms, in conjunction with the confronting walls of the vessel, a storage reservoir and an outlet flume on opposite sides of the weir. The vessel fluid inlet is located on the reservoir side of the weir member and the fluid outlet on the flume side thereof. This type of accumulator is disclosed in U.S. Pat. No. 4,041,728.
In order to improve the efficiency of refrigeration systems, it has been found desirable to cool the refrigerant leaving the condenser prior to its entering the high pressure side of the evaporator. In order to accomplish this, the prior art teaches providing a heat exchanger coil within the suction accumulator so that the relatively warm refrigerant from the condenser can be cooled through heat exchange with the relatively cool liquid refrigerant in the accumulator. In most cases, the heat exchanger simply comprises a coil disposed within the accumulator. In other cases the coil is in close proximity or in contact with the gaseous refrigerant tube, or mounted in a more remote location. Such an arrangement results in an inefficient transfer of heat between the respective fluids, and causes manufacturing problems. Prior art patents disclosing such heat exchangers include U.S. Pat. Nos. 2,393,854, 2,467,078, 2,472,729, 2,530,648, 3,021,693, 2,270,934, and 3,765,192.